Deliverability Check API

Deliverability Check API

The Deliverability Check API ensures email accuracy by validating addresses. Its syntax, domain, and mailbox checks enhance deliverability and communication reliability.

About the API:  

The Deliverability Check API is a critical tool in the digital communication landscape, designed specifically to improve the accuracy and deliverability of email communications. In the contemporary era, where email serves as the primary medium for personal and professional interactions, the importance of maintaining a reliable and efficient communication channel cannot be overstated.

Email verification, a fundamental step in the email communication process, seeks to validate the authenticity of email addresses before sending messages. Inaccurate or invalid email addresses pose problems such as bounced messages, which can negatively affect the sender's reputation and overall email deliverability. The Deliverability Check API addresses these issues systematically and automatically, providing a comprehensive solution for email address verification.

The API works through a series of meticulous checks and validations that ensure a thorough assessment of the integrity of an email address. It incorporates syntactic verification to examine the structure of the email address, confirming its adherence to standard syntax rules. Domain validation is another key component, which verifies the existence, activity and functionality of the email domain to minimize problems related to domain errors.

In addition to domain verification, the API performs mailbox validation, checking the specific mailbox associated with the email address. This process confirms the mailbox's reachability and ability to receive emails, further improving the accuracy of email delivery. The API goes beyond the basics by incorporating mechanisms to detect disposable email addresses, often associated with temporary and potentially non-serious activities.

One of the notable advantages of the Deliverability Check API is its ease of integration into various applications, websites or systems where email verification is essential. With comprehensive documentation and support, users can seamlessly incorporate the API into their workflows, contributing to the accuracy of email databases and improving the effectiveness of email marketing campaigns.

In short, the Deliverability Check API is a reliable and indispensable solution for ensuring accurate and effective email communications in today's dynamic digital environment.

What this API receives and what your API provides (input/output)?

It will receive parameters and provide you with a JSON.


What are the most common uses cases of this API?

  1. Email Marketing Campaigns: Validate email addresses before launching marketing campaigns to improve deliverability and maximize the impact of email communication.

    User Registration Processes: Implement email verification during user registration to ensure that only valid email addresses are accepted, enhancing data accuracy.

    Contact List Cleanup: Regularly verify and clean up contact lists to remove invalid or non-deliverable email addresses, maintaining a high-quality database.

    E-commerce Transactions: Validate customer email addresses during online transactions to ensure accurate order confirmations, shipping notifications, and customer communication.

    Subscription Services: Authenticate email addresses for subscription-based services to prevent the inclusion of invalid addresses in subscription lists.

Are there any limitations to your plans?


  • Basic Plan: 20,000 API Calls. 5 requests per second.

  • Pro Plan: 80,000 API Calls. 5 requests per second.

  • Pro Plus Plan: 320,000 API Calls. 5 requests per second.

  • Premium Plan: 1,000,000 API Calls. 5 requests per second.

API Documentation


To use this endpoint you must enter an email address in the parameter.


Validate Email - Endpoint Features
Object Description
email [Required]
Test Endpoint


                                                                                                                                                                                                                            {"valid_format": true, "deliverable": true, "full_inbox": false, "host_exists": true, "catch_all": false, "disposable": false, "message": "You can send messages to this Email ID", "email": "[email protected]", "domain": ""}

Validate Email - CODE SNIPPETS

curl --location --request GET '[email protected]' --header 'Authorization: Bearer YOUR_API_KEY' 


API Access Key & Authentication

After signing up, every developer is assigned a personal API access key, a unique combination of letters and digits provided to access to our API endpoint. To authenticate with the Deliverability Check API REST API, simply include your bearer token in the Authorization header.


Header Description
Authorization [Required] Should be Bearer access_key. See "Your API Access Key" above when you are subscribed.

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To use this API the user must enter an email address to validate whether it is a valid email address or not.

The Deliverability Check API is a tool designed to assess and ensure the deliverability of emails by validating the accuracy and authenticity of email addresses in real-time.

Zyla provides a wide range of integration methods for almost all programming languages. You can use these codes to integrate with your project as you need.

There are different plans suits everyone including a free trial for small amount of requests, but it’s rate is limit to prevent abuse of the service.

Zyla API Hub is like a big store for APIs, where you can find thousands of them all in one place. We also offer dedicated support and real-time monitoring of all APIs. Once you sign up, you can pick and choose which APIs you want to use. Just remember, each API needs its own subscription. But if you subscribe to multiple ones, you'll use the same key for all of them, making things easier for you.

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Yes, you can cancel your plan anytime by going to your account and selecting the cancellation option on the Billing page. Please note that upgrades, downgrades, and cancellations take effect immediately. Additionally, upon cancellation, you will no longer have access to the service, even if you have remaining calls left in your quota.

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